我有一个寻呼机全屏收集视图。当设备旋转时,collectionview的第一个单元格适合于横向和纵向模式的collectionview。但是当我在collectionview上滚动下一个单元格时,它显示了两个单元格。它并不适合所有的屏幕。虽然我滚动collectionview并旋转,但我如何将所有单元格大小适合collectionview。我试过invalideLayout()和很多方法。但我无法实现。我只是想要,尽管滚动和旋转,collectionviewcell在任何情况下都适合整个屏幕。
P.S collectionviewcell大小应该是整个屏幕大小。
public override func willTransition(to newCollection: UITraitCollection, with coordinator: UIViewControllerTransitionCoordinator) {
if UIDevice.current.orientation.isLandscape,
let layout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
let width = view.frame.height
layout.itemSize = CGSize(width: width, height: UIScreen.main.bounds.width)
layout.invalidateLayout()
} else if UIDevice.current.orientation.isPortrait,
let layout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
let width = view.frame.width
layout.itemSize = CGSize(width: width , height: UIScreen.main.bounds.height)
layout.invalidateLayout()
}
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let width = view.frame.size.width
return CGSize(width: width , height: UIScreen.main.bounds.height)
}
你必须在viewWillLayoutSubviews()中编写你的代码。像这样
override func viewWillLayoutSubviews(){super.viewWillLayoutSubviews()
guard let flowLayout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout else {
return
}
if UIDevice.current.orientation == .landscapeLeft
{
flowLayout.itemSize = CGSize(width: self.view.frame.width, height: 500)
}
else if UIDevice.current.orientation == .landscapeRight
{
flowLayout.itemSize = CGSize(width: self.view.frame.width, height: 500)
}
flowLayout.invalidateLayout()
}
你可以尝试应用以下方法吗?
第一种方法
override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
super.viewWillTransition(to: size, with: coordinator)
// YOUR CODE OR FUNCTIONS CALL HERE
}
2'方法
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.rotated), name: NSNotification.Name.UIDeviceOrientationDidChange, object: nil)
}
deinit {
NotificationCenter.default.removeObserver(self)
}
func rotated() {
if UIDevice.current.orientation.isLandscape,
let layout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
let width = view.frame.height
layout.itemSize = CGSize(width: width, height: UIScreen.main.bounds.width)
layout.invalidateLayout()
} else if UIDevice.current.orientation.isPortrait,
let layout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
let width = view.frame.width
layout.itemSize = CGSize(width: width , height: UIScreen.main.bounds.height)
layout.invalidateLayout()
}
}